随机生成字符串java

public class getRandomStrinng {
	public String getRandomString(int length) {
		String s = "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ";
		Random random = new Random();
		StringBuffer sb = new StringBuffer();
		for (int i = 0; i < length; i++) {
			int number = random.nextInt(s.length());// 随机生产一个整数，范围在[0-s.length())之间
			sb.append(s.charAt(number)); //s.charAt(number) 返回索引number的char值，append（）添加这个char到StringBuffer对象
		}
		return sb.toString();
	}
}